Pain and sleep disturbance are significant public health problems. Postoperative pain and sleep disturbance are inter-related sequelae that can adversely affect recovery if not effectively managed. Several studies have shown that the degree of postoperative pain and acute sleep disruption predict adverse health and functional outcomes, including the development of persistent pain. Postoperative opioids, while effective in attenuating pain, may exert adverse effects on sleep. Non-steroidal anti-inflammatory drugs (NSAIDs) may not provide adequate pain relief when administered as stand-alone analgesic following more invasive surgeries; however, data suggest that their adverse effects on sleep may be minimal. To-date, research has not directly compared the effects of opioid versus NSAID, alone or in combination, on acute sleep changes, time to return to baseline sleep, or subsequent pain perception. A reasonable speculation is that patients who are administered opioid plus NSAID will experience better acute pain management, fewer adverse effects on their sleep, more rapid return to baseline sleep, and lower levels of subsequent pain. The purposes of this translational research are to explore in rats who receive a postoperative analgesic regimen of opioid or NSAID or both, whether there are differences in sleep architecture, sleep continuity, time to return to baseline sleep, or mechanical sensitivity, relative to the postoperative analgesic regimen, and whether there are sex differences in these outcomes. Male and female Sprague Dawley rats who are 14-16 weeks old will be implanted with telemetric transmitters to record electroencephalogram/electromyogram biopotentials for baseline and postoperative sleep, and following recovery, will undergo the Sciatic Inflammatory Neuritis (SIN) surgery and then receive one of three postoperative analgesic regimens: 1) opioid, 2) NSAID, or 3) opioid plus NSAID. Following recovery, animals will be tested for mechanical sensitivity using von Frey filaments. This proposed research addresses areas of needed research as identified by the National Institutes of Health, the National Institute of Nursing Research, and the Institute of Medicine. Through exploring whether particular postoperative analgesic regimens are less disruptive of sleep, this proposed research has the potential to improve the quality of care to persons currently taking prescribed analgesics for pain. [unreadable] [unreadable] [unreadable]